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H. Pridalova et al.

value of fat content in milk was determined to be at 34.70 g.l'¹. Growing fat content in the course of the lactation is reported by Prasad and Sengar as well (2002). On the con-trary, Antunac (200 lb) witnessed a decrease in fat content from Day 50 to Day 100 of the lactation but after Day 150 of the lactation, its increase set in again.

Table 1. Average values for goat milk composition (gT¹) Tabela 1. Średnie wartości składu mleka kóz (gT¹)

Month	Protein	Fat	Lactose	NFS
4	23.80 + 0.50	31.60+1.80	45.20 + 0.10	73.80 ± 1.20
5	26.40 + 1.20	28.40 +2.20	45.70 + 0.50	77.40 ± 1.10
6	27.70 + 0.60	28.70+1.70	45.70 + 0.20	78.50 ± 0.50
7	28.10+1.50	27.50 + 0.40	45.30 + 0.20	79.00 ±0.20
8	27.20 ± 0.40	29.00+ 1.30	45.30 + 0.20	78.50 ± 0.60
9	27.80 ± 1.10	29.20 + 3.50	45.20 + 0.60	79.00 ± 1.40
10	29.60 + 0.70	35.70+1.50	45.20 + 0.50	80.00 ± 2.30
11	31.50 ±1.60	34.70 + 0.90	44.30 ±0.70	81.00 ±0.40
X	27.80+2.30	30.60 + 3.10	45.20 ±0.40	78.40 ± 2.20

Lactose content from Month 4 to Month 9 fluctuated mildly, values of 4.52-4.57% were found, morę significant decline was experience in Months 10 and 11 (44.20 and 44.30 gT¹). The average value of lactose content was 45.20 ± 0.40 gT¹ which corre-sponds to the data of a senes of authors: Zadrażil (2002), Gajdusek (2003), Spath and Thume (1996).

The average level of non fat solids (NFS) was 78.40 ± 2.20 gT¹. The lowest level of 73.80 gT was determined in Month 4 and the highest level of 81.00 gT in Month 11. On the whole, the content of non fat solids is Iow. Kuchtik and Sedlaćkova (2003) report a gradual increase in NFS to Day 100 of the lactation. In Day 135, they found an inconclusive decline and from then on till the end of monitoring, there was a gradual growth. The level that we found does not meet the requirements of the Slovak Technical Standard STN 57 0520 (1995) entitled „Rules on Goat Milk” that reąuires the composition of milk to have a minimum fat content of 30.0 gT¹, protein at 30.0 gT¹ and a minimum fat-free dry matter at 8.3%.

The values of physical and Chemical parameters are reported in the Table 2. Titrable acidity was at an average of 5.54 ± 0.683 °SH. Kuchtik and Sedlaćkova (2003) report that the highest value was measured at the beginning at 5.14 °SH and at the end of the lactation at 6.24 °SH, the lowest value was at 5.14 °SH in Day 100 of the lactation. Similar values are reported by Antunac (200la), too. The lowest values of our monitoring were found to be in Months 4 and 5 (4.78 and 5.00), the highest acidity was detected at the end of the lactation (6.65).

Rennetability is a technological property influenced by the lactation period. The av-erage value of 93.33 ± 14.76 s was found, the highest value of 104.8 and 123.00 s in Months 8 and 9, the lowest value of 76.83 s in Month 6. Kuchtik and Sedlaćkova (2003) present the values of 50-134 s.

Acta Sci. Pol.